内蒙古草地样带地上生物量变化

Changes in aboveground biomass of grasssland transect in Inner Mongolia Autonomous Region,China

采用草地植被群落学调查方法,对内蒙古东北-西南草地样带典型区草地地上生物量变化进行了测量、计算和分析。研究表明,1)内蒙古东北―西南草地样带上草地背景点地上生物量在50～80g.m-2;自东向西,随着区域植被类型由温性草甸草原向温性典型草原和温性荒漠草原演变,背景点草地地上生物量逐渐减小。2)受草地开垦、耕地撂荒、耕地退耕还林还草等土地利用活动的影响,包含全部物种的草地地上生物量与土地利用强度之间没有严格的对应关系;但是,可食牧草地上生物量以及可食牧草比率随土地利用强度的增加而逐步减少。3)在生态系统质量和功能评估中,单纯应用草地地上生物量指标存在很大的局限性,可食牧草地上生物量指标以及可食牧草比率指标在应用中更有意义。

The plant coenology survey has done in northeast-southwest grassland transect in Inner Mongolia by using method of transect-sample area-quadrat.Then based on the results of both indoor and outdoor investments and measures,the gradient changes of aboveground biomass were analyzed.The main conclusions are as follows：（1） the background biomass along the northeast-southwest transects in Inner Mongolia ranges from 50-80 g·m-2;the value of grassland＇s aboveground biomass reduced with the change of vegetation type.It shifts from meadow steppe to typical steppe and desert steppe.（2） the total aboveground biomass of grassland has no strict corresponding relation with the land use intensity because of the impacts of human activities such as farming,field＇s abandoned and returning reclaimed land and forests and so on.But the biomass value of essbar perennation plant is declining with the intensity of land use.（3） using aboveground biomass to evaluate the quality and health of the ecosystem was partly limited.The percentage of biomass value in different land use intensity quadrat and background quadrat could hit the aim of rejecting the impacts of natural geographical area,regional climate background,and could analysis the influence of economic performance and economic structure development on the grassland ecosystem.